Area Code +81-503-(3740000...3749999) located in VoIP, more detail is as below. Place International Dialing Code : 81 International Prefix : 010 National Prefix : 0 National Destination Code : 503 Subscriber Number From : 3740000 Subscriber Number To : 3749999 National Destination Code Length : 3 Uses National Destination Code : Yes National Significant Number Length : 10 Number Type : V (VoIP, Location Independent fixed land line) Carrier Name : NTT Communications Click here to buy Japan Area Code Database Other Information Language Code : ja (Japanese) Country Number : 392 (Japan) Country Code : JP (Japan) City : VoIP Timezone : Asia/Tokyo Coordinated Universal Time : +09:00 Daylight Saving Time : No National Significant Number Minimum Length : 10 Latitude : None Longitude : None ‹ previous : +81-503-(3730000...3739999) next › : +81-503-(3750000...3759999) Dialling Instructions For trunk calls: 0 503 3740000 (Trunk Code + National Destination Code + Subscriber Number) For international calls: 010 81 503 3740000 (International Prefix + International Dailing Code +National Destination Code + Subscriber Number) Telephone Number List 3740000 ~ 3749999 (Count: 10,000) Example: +81-503-3740000 / 01081-503-3740000 (0503-3740000 / 0-503-3740000) +81-503-3740001 / 01081-503-3740001 (0503-3740001 / 0-503-3740001) +81-503-3740002 / 01081-503-3740002 (0503-3740002 / 0-503-3740002) +81-503-3740003 / 01081-503-3740003 (0503-3740003 / 0-503-3740003) +81-503-3740004 / 01081-503-3740004 (0503-3740004 / 0-503-3740004) ...+81-503-xxxxxxx / 01081-503-xxxxxxx (0503-xxxxxxx / 0-503-xxxxxxx) ...+81-503-3749995 / 01081-503-3749995 (0503-3749995 / 0-503-3749995) +81-503-3749996 / 01081-503-3749996 (0503-3749996 / 0-503-3749996) +81-503-3749997 / 01081-503-3749997 (0503-3749997 / 0-503-3749997) +81-503-3749998 / 01081-503-3749998 (0503-3749998 / 0-503-3749998) +81-503-3749999 / 01081-503-3749999 (0503-3749999 / 0-503-3749999)